Final answer:
The sudden spike in body temperature observed after an EGD in a patient with GERD could be due to infection.
Step-by-step explanation:
The sudden spike in body temperature observed after an esophagogastroduodenoscopy (EGD) in a patient with gastroesophageal reflux disease (GERD) could be due to infection. Infections of the gastrointestinal tract can cause symptoms such as nausea, vomiting, diarrhea, and fever. Therefore, it is important to monitor the patient for signs of infection and seek appropriate medical intervention if necessary.